The lens includes a small piece of circuitry that measures
glucose levels from the tears that naturally lubricate the eye. It
also includes a wireless sensor, which Google has stated could be
used to communicate data collected with an app.

Tears were chosen, Google has explained, as they are one of numerous fluids the
body produces alongside blood that can carry details of a person's
glucose levels. The use of a contact lens may transpire to be an
easier way to monitor these levels, and potentially display the
results to a wearer using small LED lights that blink when readings
are above or below a healthy threshold.

Google has said it has completed several studies to advance
development of a prototype, which currently reads glucose levels
once per second. The company is also in talks with the US Food and
Drug Administration (FDA) to bring the technology to US diabetes
sufferers in future. The company has not commented on any
UK-specific launch or testing, although Wired.co.uk understands
talks have taken place with British medical charities.

It is estimated that three million people in the UK have Type 1
or Type 2 diabetes, with a further 850,000 suffering without
diagnosis. Most home monitoring involves pricking the finger to
extract a drop of blood, and using strips of material or a machine
to determine the current status of glucose levels.